Adrenal Mass Biopsy in Patients Without Extraadrenal Primary Malignancy: A Multicenter Study

BACKGROUND. Adrenal washout CT is not useful for evaluating incidental adrenal masses in patients without known or suspected primary extraadrenal malignancy. OBJECTIVE. The purpose of our study was to evaluate the diagnostic utility of adrenal mass biopsy in patients without known or suspected extraadrenal primary malignancy. METHODS. This retrospective six-center study included 69 patients (mean age, 56 years; 32 men, 37 women) without known or suspected extraadrenal primary malignancy who underwent image-guided core needle biopsy between January 2004 and June 2021 of a mass suspected to be arising from the adrenal gland. Biopsy results were classified as diagnostic or nondiagnostic. For masses resected after biopsy, histopathologic concordance was assessed between diagnoses from biopsy and resection. Masses were classified as benign or malignant by resection or imaging follow-up, and all nondi-agnostic biopsies were classified as false results. RESULTS. The median mass size was 7.4 cm (range, 1.9-19.2 cm). Adrenal mass biopsy had a diagnostic yield of 64% (44/69; 95% CI, 51-75%). After biopsy, 25 masses were resected, and 44 had imaging follow-up. Of the masses that were resected after diagnostic biopsy, diagnosis was concordant between biopsy and resection in 100% (12/12). Of the 13 masses that were resected after nondiagnostic biopsy, the diagnosis from re-section was benign in eight masses and malignant in five masses. The 44 masses with imaging follow-up included one mass with diagnostic biopsy yielding benign adenoma and two masses with nondiagnostic biopsy results that were classified as malignant by imaging follow-up. Biopsy had overall sensitivity and specificity for malignancy of 73% (22/30) and 54% (21/39), respectively; diagnostic biopsies had sensitivity and specificity for malignancy of 96% (22/23) and 100% (21/21), respectively. Among nine nondi-agnostic biopsies reported as adrenocortical neoplasm, six were classified as malignant by the reference standard (resection showing adrenocortical carcinoma in four, resection showing adrenocortical neoplasm of uncertain malignant potential in one, imaging follow-up consistent with malignancy in one). CONCLUSION. Adrenal mass biopsy had low diagnostic yield, with low sensitivity and low specificity for malignancy. A biopsy result of adrenocortical neoplasm did not reliably differentiate benign and malignant adrenal masses. CLINICAL IMPACT. Biopsy appears to have limited utility for the evaluation of incidental adrenal masses in patients without primary extraadrenal malignancy.

Is There Evidence of P-Hacking in Imaging Research?

BACKGROUND

P-hacking, the tendency to run selective analyses until they become significant, is prevalent in many scientific disciplines.

PURPOSE

This study aims to assess if p-hacking exists in imaging research.

METHODS

Protocol, data, and code available here https://osf.io/xz9ku/?view_only=a9f7c2d841684cb7a3616f567db273fa. We searched imaging journals Ovid MEDLINE from 1972 to 2021. Text mining using Python script was used to collect metadata: journal, publication year, title, abstract, and P-values from abstracts. One P-value was randomly sampled per abstract. We assessed for evidence of p-hacking using a p-curve, by evaluating for a concentration of P-values just below .05. We conducted a one-tailed binomial test (α = .05 level of significance) to assess whether there were more P-values falling in the upper range (e.g., .045 < P < .05) than in the lower range (e.g., .04 < P < .045). To assess variation in results introduced by our random sampling of a single P-value per abstract, we repeated the random sampling process 1000 times and pooled results across the samples. Analysis was done (divided into 10-year periods) to determine if p-hacking practices evolved over time.

RESULTS

Our search of 136 journals identified 967,981 abstracts. Text mining identified 293,687 P-values, and a total of 4105 randomly sampled P-values were included in the p-hacking analysis. The number of journals and abstracts that were included in the analysis as a fraction and percentage of the total number was, respectively, 108/136 (80%) and 4105/967,981 (.4%). P-values did not concentrate just under .05; in fact, there were more P-values falling in the lower range (e.g., .04 < P < .045) than falling just below .05 (e.g., .045 < P < .05), indicating lack of evidence for p-hacking. Time trend analysis did not identify p-hacking in any of the five 10-year periods.

CONCLUSION

We did not identify evidence of p-hacking in abstracts published in over 100 imaging journals since 1972. These analyses cannot detect all forms of p-hacking, and other forms of bias may exist in imaging research such as publication bias and selective outcome reporting.

Unconstrained generation of synthetic antibody-antigen structures to guide machine learning methodology for antibody specificity prediction

Machine learning (ML) is a key technology for accurate prediction of antibody-antigen binding. Two orthogonal problems hinder the application of ML to antibody-specificity prediction and the benchmarking thereof: the lack of a unified ML formalization of immunological antibody-specificity prediction problems and the unavailability of large-scale synthetic datasets to benchmark real-world relevant ML methods and dataset design. Here we developed the Absolut! software suite that enables parameter-based unconstrained generation of synthetic lattice-based three-dimensional antibody-antigen-binding structures with ground-truth access to conformational paratope, epitope and affinity. We formalized common immunological antibody-specificity prediction problems as ML tasks and confirmed that for both sequence- and structure-based tasks, accuracy-based rankings of ML methods trained on experimental data hold for ML methods trained on Absolut!-generated data. The Absolut! framework has the potential to enable real-world relevant development and benchmarking of ML strategies for biotherapeutics design.

Novel bioreactor internals for the cultivation of spore‐forming fungi in pellet form

This study introduced an automated long‐term fermentation process for fungals grown in pellet form. The goal was to reduce the overgrowth of bioreactor internals and sensors while better rheological properties in the fermentation broth, such as oxygen transfer and mixing time, can be achieved. Because this could not be accomplished with continuous culture and fed‐batch fermentation, repeated‐batch fermentation was implemented with the help of additional bioreactor internals (“sporulation supports”). This should capture some biomass during fermentation. After harvesting the suspended biomass, intermediate cleaning was performed using a cleaning device. The biomass retained on the sporulation support went through the sporulation phase. The spores were subsequently used as inocula for the next batch. The reason for this approach was that the retained pellets could otherwise cause problems (e.g., overgrowth on sensors) in subsequent batches because the fungus would then show undesirable hyphal growth. Various sporulation supports were tested for sufficient biomass fixation to start the next batch. A reproducible spore concentration within the range of the requirements could be achieved by adjusting the sporulation support (design and construction material), and an intermediate cleaning adapted to this.

Progress and challenges for the machine learning-based design of fit-for-purpose monoclonal antibodies

Although the therapeutic efficacy and commercial success of monoclonal antibodies (mAbs) are tremendous, the design and discovery of new candidates remain a time and cost-intensive endeavor. In this regard, progress in the generation of data describing antigen binding and developability, computational methodology, and artificial intelligence may pave the way for a new era of in silico on-demand immunotherapeutics design and discovery. Here, we argue that the main necessary machine learning (ML) components for an in silico mAb sequence generator are: understanding of the rules of mAb-antigen binding, capacity to modularly combine mAb design parameters, and algorithms for unconstrained parameter-driven in silico mAb sequence synthesis. We review the current progress toward the realization of these necessary components and discuss the challenges that must be overcome to allow the on-demand ML-based discovery and design of fit-for-purpose mAb therapeutic candidates.

In silico proof of principle of machine learning-based antibody design at unconstrained scale

Generative machine learning (ML) has been postulated to become a major driver in the computational design of antigen-specific monoclonal antibodies (mAb). However, efforts to confirm this hypothesis have been hindered by the infeasibility of testing arbitrarily large numbers of antibody sequences for their most critical design parameters: paratope, epitope, affinity, and developability. To address this challenge, we leveraged a lattice-based antibody-antigen binding simulation framework, which incorporates a wide range of physiological antibody-binding parameters. The simulation framework enables the computation of synthetic antibody-antigen 3D-structures, and it functions as an oracle for unrestricted prospective evaluation and benchmarking of antibody design parameters of ML-generated antibody sequences. We found that a deep generative model, trained exclusively on antibody sequence (one dimensional: 1D) data can be used to design conformational (three dimensional: 3D) epitope-specific antibodies, matching, or exceeding the training dataset in affinity and developability parameter value variety. Furthermore, we established a lower threshold of sequence diversity necessary for high-accuracy generative antibody ML and demonstrated that this lower threshold also holds on experimental real-world data. Finally, we show that transfer learning enables the generation of high-affinity antibody sequences from low-N training data. Our work establishes a priori feasibility and the theoretical foundation of high-throughput ML-based mAb design.

Safety and efficacy of flecainide associated with beta-blockers in arrhythmogenic right ventricular cardiomyopathy

AIMS

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy associated with a high risk of ventricular arrhythmia (VA). Current guidelines recommend beta-blockers as first-line medical therapy and if ineffective, sotalol or amiodarone. We describe our experience, as a tertiary centre for ARVC, with the effectiveness and tolerance of flecainide in addition to beta-blockers to prevent VA in ARVC.

METHODS AND RESULTS

We retrospectively included 100 consecutive ARVC patients who received flecainide with beta-blockers between May 1999 and November 2017. Treatment persistence and related side effects were assessed, as was VA-free survival on treatment, 24-h Holter monitoring and programmed ventricular stimulation (PVS) off- and on-treatment. Tolerance was good, with 10% flecainide discontinuations (lack of efficacy in six, atrial fibrillation in one, and side effects in three). No Brugada-induced electrocardiography pattern on flecainide or haemodynamic impairment was reported. Premature ventricular contraction burden at 24-h Holter monitoring was significantly decreased under treatment [median 415 (interquartile range, IQR 97-730) vs. 2370 (1572-3400) at baseline, P < 0.0001, n = 46]. Among the 33 patients with PVS under treatment, PVS was positive in 40% on-treatment vs. 94% off-treatment (P < 0.001). During a median follow-up of 47 months (IQR 23-73), 22 patients presented sustained VA on treatment, corresponding to an event rate of 5% [95% confidence interval (CI) (0.6-9)] at 1 year and 25% [95% CI (14-35)] at 5 years under treatment. No patient died.

CONCLUSION

This study suggests that flecainide and beta-blockers association is complementary to implantable cardioverter-defibrillator and catheter ablation and is safe for treating persistent symptomatic VA in patients with ARVC.

Documentation of Shared Decisionmaking in the Emergency Department

STUDY OBJECTIVE

While patient-centered communication and shared decisionmaking are increasingly recognized as vital aspects of clinical practice, little is known about their characteristics in real-world emergency department (ED) settings. We constructed a natural language processing tool to identify patient-centered communication as documented in ED notes and to describe visit-level, site-level, and temporal patterns within a large health system.

METHODS

This was a 2-part study involving (1) the development and validation of an natural language processing tool using regular expressions to identify shared decisionmaking and (2) a retrospective analysis using mixed effects logistic regression and trend analysis of shared decisionmaking and general patient discussion using the natural language processing tool to assess ED physician and advanced practice provider notes from 2013 to 2020.

RESULTS

Compared to chart review of 600 ED notes, the accuracy rates of the natural language processing tool for identification of shared decisionmaking and general patient discussion were 96.7% (95% CI 94.9% to 97.9%) and 88.9% (95% confidence interval [CI] 86.1% to 91.3%), respectively. The natural language processing tool identified shared decisionmaking in 58,246 (2.2%) and general patient discussion in 590,933 (22%) notes. From 2013 to 2020, natural language processing-detected shared decisionmaking increased 300% and general patient discussion increased 50%. We observed higher odds of shared decisionmaking documentation among physicians versus advanced practice providers (odds ratio [OR] 1.14, 95% CI 1.07 to 1.23) and among female versus male patients (OR 1.13, 95% CI 1.11 to 1.15). Black patients had lower odds of shared decisionmaking (OR 0.8, 95% CI 0.84 to 0.88) compared with White patients. Shared decisionmaking and general patient discussion were also associated with higher levels of triage and commercial insurance status.

CONCLUSION

In this study, we developed and validated an natural language processing tool using regular expressions to extract shared decisionmaking from ED notes and found multiple potential factors contributing to variation, including social, demographic, temporal, and presentation characteristics.

Effects of feed particle size on energy values for broiler chickens at various ages

The objective of this study was to evaluate the effects of various geometric mean diameters (GMDs) of particles of corn, pelleted soybean meal and a corn-soy mixture in the proportion of 70% and 30%, respectively, on the nutritional value of the feeds. The study evaluated energy consumption, the contents of apparent metabolizable energy (AME) and AME corrected for nitrogen balance (AMEn) and the metabolizability coefficients for broiler chickens at various ages. A total of 540 Cobb 500 male broilers were housed in metabolic cages (experimental units). Trials were performed separately with each feed. A completely randomized design was used with four treatments, namely corn with 573, 636, 851, and 1012 μm GMDs; pelleted soybean meal with 538, 550, 665, and 741 μm GMDs; and the corn-soy mixture with 627, 658, 893, and 1040 μm GMDs. Birds were evaluated on days 1 - 10, 11 - 20, 21 - 30, and 31 - 40. Larger GMDs resulted in lower energy consumption. From 1 to 10 days, birds consumed less metabolizable energy than older birds. Birds fed corn from days 1 to 10 had higher metabolizable energy (P <0.05) with increasing GMD up to 1042 μm. However, the results varied, depending on the feed and its combinations. The use of coarse particles could reduce the costs of grinding, and would have few effects on the metabolizable energy of broiler chickens.

Mechanisms of torsade de pointes tachycardia in patients with spontaneous high-degree atrioventricular block: A modern look at old data

INTRODUCTION

The mechanisms of torsade de pointes tachycardia (TdP) are incompletely understood. We aimed to investigate the mechanisms underlying TdP tachycardia in patients with spontaneous high-degree atrioventricular block (AVB).

METHODS AND RESULTS

This retrospective study reviewed old TdP recordings after ventricular temporary pacing interruption in 16 patients with spontaneous high-degree AVB. Five of them had also bipolar endocardial right ventricular (RV) apex recordings. The QT interval during AVB at a mean heart rate of 38.9 ± 7.5 bpm was 653.0 ± 67.2 ms. The critical coupling interval (CCI) between the last escape QRS during AVB and the first premature ventricular complex (PVC) was significantly shorter before the onset of TdP than before single PVCs and couplets. A morphologic crescendo of the escape T wave was observed before the onset of TdP, followed by a rhythmic and morphologic crescendo of PVCs. The escape RV apex electrograms (EGMs) showed the constant pattern of a rapid deflection similar to a Purkinje potential 40 to 80 ms after the onset of the QRS, superimposed on a smooth low amplitude signal in 4 out of 5 patients.

CONCLUSIONS

The major endocardial T wave prolongation and augmentation (morphologic crescendo) of the escape beat prior to the first PVC suggests a phase 2 reentry mechanism due to early afterdepolarization. The induced TdP can be due to the changing outputs from one or two simultaneous RV moving reentry circuits between depressed fibers and fast conducting ones, possibly located in the thin crista supraventricularis structure which has several connections with the septum and the RV free wall.

Completeness of Reporting of Systematic Reviews of Diagnostic Test Accuracy Based on the PRISMA-DTA Reporting Guideline

BACKGROUND

We evaluated the completeness of reporting of diagnostic test accuracy (DTA) systematic reviews using the recently developed Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA)-DTA guidelines.

METHODS

MEDLINE® was searched for DTA systematic reviews published October 2017 to January 2018. The search time span was modulated to reach the desired sample size of 100 systematic reviews. Reporting on a per-item basis using PRISMA-DTA was evaluated.

RESULTS

One hundred reviews were included. Mean reported items were 18.6 of 26 (71%; SD = 1.9) for PRISMA-DTA and 5.5 of 11 (50%; SD = 1.2) for PRISMA-DTA for abstracts. Items in the results were frequently reported. Items related to protocol registration, characteristics of included studies, results synthesis, and definitions used in data extraction were infrequently reported. Infrequently reported items from PRISMA-DTA for abstracts included funding information, strengths and limitations, characteristics of included studies, and assessment of applicability. Reporting completeness was higher in higher impact factor journals (18.9 vs 18.1 items; P = 0.04), studies that cited PRISMA (18.9 vs 17.7 items; P = 0.003), or used supplementary material (19.1 vs 18.0 items; P = 0.004). Variability in reporting was associated with author country (P = 0.04) but not journal (P = 0.6), abstract word count limitations (P = 0.9), PRISMA adoption (P = 0.2), structured abstracts (P = 0.2), study design (P = 0.8), subspecialty area (P = 0.09), or index test (P = 0.5). Abstracts with a higher word count were more informative (R = 0.4; P &lt; 0.001). No association with word counts was observed for full-text reports (R = −0.03; P = 0.06).

CONCLUSIONS

Recently published reports of DTA systematic reviews are not fully informative when evaluated against the PRISMA-DTA guidelines. These results should guide knowledge translation strategies, including journal level (e.g., PRISMA-DTA adoption, increased abstract word count, and use of supplementary material) and author level (PRISMA-DTA citation awareness) strategies.

Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D) - What We Have Learned after 40 Years of the Diagnosis of This Clinical Entity

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) was initially recognized as a clinical entity by Fontaine and Marcus, who evaluated a group of patients with ventricular tachyarrhythmia from a structurally impaired right ventricle (RV). Since then, there have been significant advances in the understanding of the pathophysiology, manifestation and clinical progression, and prognosis of the pathology. The identification of genetic mutations impairing cardiac desmosomes led to the inclusion of this entity in the classification of cardiomyopathies. Classically, ARVC/D is an inherited disease characterized by ventricular arrhythmias, right and / or left ventricular dysfunction; and fibro-fatty substitution of cardiomyocytes; its identification can often be challenging, due to heterogeneous clinical presentation, highly variable intra- and inter-family expressiveness, and incomplete penetrance.

In the absence of a gold standard that allows the diagnosis of ARVC/D, several diagnostic categories were combined and recently reviewed for a higher diagnostic sensitivity, without compromising the specificity. The finding that electrical abnormalities, particularly ventricular arrhythmias, usually precede structural abnormalities is extremely important for risk stratification in positive genetic members. Among the complementary exams, cardiac magnetic resonance imaging (CMR) allows the early diagnosis of left ventricular impairment, even before morpho-functional abnormalities. Risk stratification remains a major clinical challenge, and antiarrhythmic drugs, catheter ablation and implantable cardioverter defibrillator are the currently available therapeutic tools. The disqualification of the sport prevents cases of sudden death because the effort can trigger not only the electrical instability, but also the onset and progression of the disease.

Right atrial pathology in arrhythmogenic right ventricular dysplasia

BACKGROUND

Atrial fibrillation (AF) is the most common atrial arrhythmia in arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD). Considering the histologic changes known in the right ventricular (RV) in ARVD, the aim of the present study was to examine right atrial (RA) pathology in patients with ARVD.

METHODS

Histology of RA and RV was assessed from autopsy material in 3 patients with ARVD without persistent atrial arrhythmia. RA histology in 3 patients with permanent AF without ARVD and 5 patients without cardiovascular disease was also studied. Staining with hematoxylin phloxine saffron was performed for the ARVD patients to identify fibrosis, and hematoxylin-eosin for identification of lymphocytes. Masson's trichrome staining was performed for control groups taken from a collection of standard glass slides.

RESULTS

In all 3 ARVD cases, RA anomalies were observed that revealed a reduction of cardiomyocytes, the presence of adipocytes, some of them inside the mediomural atrial layer and interstitial fibrosis. In 2 ARVD cases, interstitial fibrosis was also associated with a focus of replacement fibrosis, which was also observed in patients with permanent AF without ARVD. The histologic specimen of the RA and RV from the control group without cardiovascular disease did not display any evidence of fat or fibrosis with a preserved cardiomyocyte architecture.

CONCLUSIONS

A similar histopathological substrate, as can be observed in the RV of patients with ARVD can also be seen in the RA of these patients. This may explain the high prevalence of atrial arrhythmias, particularly AF, in patients with ARVD.

Fragmented endocardial signals and early afterdepolarizations during torsades de pointes tachycardia

BACKGROUND

Bradycardia-induced torsade de pointes (TdP) tachycardia in patients with spontaneous high-degree atrioventricular block (AVB) is common. The aim of this study was to analyze endocardial recordings during TdP in spontaneous high-degree AVB in humans to better understand the electrophysiological mechanisms underlying this phenomenon.

METHODS

The study group consisted of 5 patients with typical episodes of TdP during spontaneous high-degree AVB. A standard (USCI) temporary bipolar endocardial catheter positioned at the apex of the right ventricle (RV) and bipolar chest leads from two precordial leads V1 and V4 were used to record the tracings during TdP.

RESULTS

The presence of a wide spectrum of fragmentations was noted on endocardial electrograms (EGMs), which were invisible on the surface electrocardiogram (ECG) tracing. Endocardial signals indicated that TdP started in the proximity of the RV apex, since the local EGM began prior to the QRS complex on the surface ECG. Early afterdepolarizations (EADs) were observed in 2 out of 5 cases confirming a common opinion about the mechanism of TdP. However, this phenomenon was not observed in 3 other patients suggesting that the arrhythmia was the result of a different mechanism originating in proximity to the RV apex.

CONCLUSIONS

This work demonstrated early endocardial signals in the RV apex during TdP associated with high-degree AVB in humans, and exhibits a spectrum of fragmented signals in this area occurring on a single or multiple beats. These fragmentations indicate areas of poor conduction and various degrees of intramyocardial block, and therefore a new mechanism of TdP tachycardia in some patients with spontaneous high-degree AVB.

Epsilon waves: Milestones in the discovery and progress

The Epsilon wave was first identified in 1977. Four decades of progress help people to better understand its pathological electrogenesis and diagnostic value. Currently, the Epsilon wave is on the list of the 2010 Task Force recommendations for the diagnosis of arrhythmogenic right ventricular dysplasia (ARVD). In this review, we provide the history of the first recording of the Epsilon wave in coronary artery disease and Uhl's anomaly, subsequently leading to the signal averaging technique to record late potentials. Based on our experience, we discuss some existing controversies. When we look back at the decades of progress of the Epsilon wave, we conclude that the Epsilon wave is only the tip of the iceberg of ECG abnormalities in ARVD.

Epsilon wave on an electronic loop in a case of arrhythmogenic right ventricular dysplasia with myocarditis: an updated definition of the Epsilon wave

A young man presented with a history of myocarditis with palpitations and dizziness. He had implantation of a loop recorder that showed repetitive short episodes of VT. In addition, there were fragmented potentials immediately following the large and sharp electrograms (EGMs) before as well as after episodes of VT suggesting an Epsilon wave. This signal can be observed in multiple cardiac conditions including coronary artery disease. It was originally recorded on the epicardium as well as on the endocardium. However, in ARVD it can be defined as an electric signal observed after the end of the QRS complex in the right as opposed to the left precordial leads (difference ≥ 25 ms). It can also be an aid to the diagnosis of patients with ARVD who have other signs or symptoms suggesting ARVD including episodes of myocarditis. This potential consists of a slurring at the end of the QRS complex or an independent potential after the return to the isoelectric line. It can be better observed by increasing amplification of the ECG tracing as well as double speed using the Fontaine lead system. Epsilon wave too small to be recorded on the standard ECG can be extracted by Signal Averaging ECG SAECG).

Impaired detection and differentiation of briefly presented facial emotions in adults with high-functioning autism and asperger syndrome

Although deficits in the recognition of emotional facial expressions are considered a hallmark of autism spectrum disorder (ASD), characterization of abnormalities in the differentiation of emotional expressions (e.g., sad vs. angry) has been rather inconsistent, especially in adults without intellectual impairments who may compensate for their deficits. In addition, previous research neglected the ability to detect emotional expressions (e.g., angry vs. neutral). The present study used a backward masking paradigm to investigate, a) the detection of emotional expressions, and b) the differentiation of emotional expressions in adults diagnosed with high functioning autism or Asperger syndrome (n = 23) compared to neurotypical controls (n = 25). Compensatory strategies were prevented by shortening the stimulus presentation time (33, 67, and 100 ms). In general, participants with ASD were significantly less accurate in detecting and differentiating emotional expressions compared to the control group. In the emotion differentiation task, individuals with ASD profited significantly less from an increase in presentation time. These results reinforce theoretical models that individuals with ASD have deficits in emotion recognition under time constraints. Furthermore, first evidence was provided that emotion detection and emotion differentiation are impaired in ASD.

Catheter ablation of organized atrial arrhythmias in orthotopic heart transplantation

BACKGROUND

Organized atrial arrhythmias (OAAs) are common after orthotopic heart transplantation (OHT). Some controversies remain about their clinical presentation, relationship with atrial anastomosis and electrophysiologic features. The objectives of this retrospective study were to determine the mechanisms of OAAs after OHT and describe the outcomes of radiofrequency catheter ablation (RFCA).

METHODS

Thirty consecutive transplanted patients (mean age 48 ± 17 years, 86.6% male) underwent 3-dimensional electroanatomic mapping and RFCA of their OAA from 2004 to 2012 at our center.

RESULTS

Twenty-two patients had biatrial anastomosis and 8 had bicaval anastomosis. Macro-reentry was the arrhythmia mechanism for 96% of patients. The electrophysiologic diagnoses were: cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) in 93% of patients (n = 28); perimitral AFL in 3% (n = 1); and focal atrial tachycardia (FAT) in 3% (n = 1). In 5 patients with biatrial anastomosis, a right FAT was inducible. Primary RFCA success was obtained in 93% of patients. Mean follow-up time was 39 ± 26.8 months. Electrical repermeation between recipient and donor atria, present in 20% of patients (n = 6), did not account for any of the OAAs observed. Survival without OAA relapse at 12, 24 and 60 months was 93%, 89% and 79%, respectively.

CONCLUSIONS

CTI-dependent AFL accounted for most instances of OAA after OHT, regardless of anastomosis type. Time from transplantation to OAA was shorter with bicaval than with biatrial anastomosis. RFCA was safe and provided good long-term results.

Hypo-methylation mediates chromosomal instability in pancreatic NET

DAXX and or ATRX loss occur in 40% of pancreatic neuroendocrine tumors (PanNETs). PanNETs negative for DAXX or ATRX show an increased risk of relapse. The tumor-associated pathways activated upon DAXX or ATRX loss and how this event may induce chromosomal instability (CIN) and alternative lengthening telomeres (ALT) are still unknown. Both DAXX and ATRX are involved in DNA methylation regulation. DNA methylation of heterochromatin and of non-coding sequences is extremely important for the maintenance of genomic stability. We analyzed the association of DAXX and/or ATRX loss and CIN with global DNA methylation in human PanNET samples and the effect of DAXX knock-down on methylation and cell proliferation. We assessed LINE1 as well as global DNA methylation in 167 PanNETs, and we found that DAXX and or ATRX-negative tumors and tumors with CIN were hypomethylated. DAXX knock-down in PanNET cell lines blocked cells in G1/G0 phase and seemed to increase CIN in QGP-1 cells. However, no direct changes in DNA methylation were observed after DAXX knock-down in vitro In conclusion, our data indicate that epigenetic changes are crucial steps in the progression of PanNETs loss and suggest that DNA methylation is the mechanism via which CIN is induced, allowing clonal expansion and selection.

[A child with a fever and rash]

A 1-year-old boy with flu-like symptoms and red papules, vesicles and macules around the mouth, on the extremities, on the palms of his hands and soles of the feet was seen at the outpatient clinic. He was diagnosed with an atypical form of hand, foot, and mouth disease, which can present itself in various forms.

Determinação dos valores energéticos e aminoacídicos da silagem de grãos úmidos de milho para frangos de corte

Para a determinação dos valores energéticos da silagem de grãos úmidos de milho (SGUM), foram utilizados 120 frangos de corte machos, linhagem Cobb Slow, de 21 a 31 dias de idade, com peso médio inicial de 765,0±1,7 g, distribuídos em um delineamento inteiramente casualizado, com cinco tratamentos (ração referência-RR e níveis de substituição da SGUM de 10, 20, 30 e 40 %), seis repetições e quatro aves por unidade experimental. O período experimental teve duração de dez dias, sendo cinco de adaptação e cinco de coleta. O método de análise foi o de coleta total de excretas, para posterior análises de energia metabolizável aparente (EMA) e EMA corrigida pelo balanço de nitrogênio (EMAn) da SGUM. Para a determinação dos valores de aminoácidos, foi usada a técnica de alimentação forçada em 12 galos Leghorn cecectomizados, com peso médio de 1912,10±133,73 g. Seis animais receberam a SGUM e os outros seis permaneceram em jejum. Ao final do período de coleta de excretas, foi determinado o perfil de aminoácidos essenciais, coeficientes de digestibilidade verdadeira e o conteúdo digestível verdadeiro dos aminoácidos no alimento. A SGUM apresentou valores médios de EMA e EMAn de 2283 de 2272 kcal/kg, respectivamente, sendo que os valores energéticos foram negativamente influenciados pelos níveis de inclusão da SGUM. A cistina apresentou o menor coeficiente de digestibilidade, enquanto a leucina e a glutamina apresentaram os maiores valores de aminoácidos digestíveis.

Digestibilidade de nutrientes em rações de frangos de corte suplementadas com promotores de crescimento

Um experimento foi realizado para avaliar o efeito da utilização de diferentes promotores de crescimento sobre o metabolismo de frangos de corte em crescimento. Foram avaliadas duas dietas, uma atendendo às exigências nutricionais de frangos de corte (normal) e uma dieta reduzida, com 5% a menos da exigência nutricional (reduzida), suplementadas ou não com antibióticos e prebióticos. Foram utilizados 180 pintos de corte criados em galpão convencional, com cama de maravalha, até os 21 dias de idade. Em seguida, foram divididos em 36 gaiolas, distribuídos em delineamento experimental inteiramente ao acaso, utilizando método tradicional de coleta de excretas. Houve interação (P<0,05) entre dieta e promotores de crescimento para os coeficientes de digestibilidade ileal da matéria seca (CDIMS), da proteína bruta (CDIPB) e do extrato etéreo (CDIEE). A dieta reduzida contendo antibiótico apresentou menor CDIMS. A dieta normal contendo antibiótico apresentou maior CDIPB (P<0,05), enquanto a dieta reduzida contendo prebiótico apresentou melhor CDIPB e CDIEE (P<0,05). Os valores dos coeficientes de digestibilidade total da matéria seca (CDTMS), da proteína bruta (CDTPB) e do extrato etéreo (CDTEE) apresentaram interação (P<0,05) entre dietas e promotores de crescimento, em que a dieta reduzida contendo antibiótico apresentou menor CDTMS e CDTEE. A dieta normal apresentou maiores valores de energia metabolizável aparente (EMA) e EMA corrigida para balanço de nitrogênio (EMAn) (P<0,05). Concluiu-se que, ao se reduzir a exigência nutricional da ração, a digestibilidade dos nutrientes foi reduzida, no entanto os óleos essenciais promoveram aumento nos coeficientes de digestibilidade ileal da matéria seca, da proteína bruta e do extrato etéreo.

Abstract WP37: Whole Brain CT Perfusion Identifies Ischemic Events in Patients With Mild Neurological Symptoms

Introduction: More than half of ischemic stroke patients present as minor strokes (NIHSS<6). A lack of thrombolysis guidelines for this population leads to untreated strokes and erroneously treated stroke mimics, producing adverse outcomes. Data suggest that whole brain CT perfusion (WB-CTP) improves detection of ischemia, offering a potential method of ameliorating diagnostic uncertainty in these patients.

Hypothesis: WB-CTP can guide clinical decisions by identifying patients with ischemic episodes that would benefit from thrombolysis or early intervention.

Methods: This retrospective chart review enrolled 524 consecutive patients receiving WB-CTP with a Toshiba 320 detector scanner between 08/2008 and 06/2015, for acute stroke less than 6 hours from onset and NIHSS<6, and who showed no evidence of intracranial hemorrhage. Patients were excluded for non-diagnostic (n=25) or unreported (n=8) scans and non-ischemic findings (7). For diagnostic accuracy calculations, the reference standard was the final clinical impression suggesting ischemic events, as only 52% had follow-up imaging. Subgroup analyses were performed in patients receiving follow-up imaging.

Results: A total of 484 patients (age 17-101, 54% men, mean NIHSS 2.47) were included. Follow-up imaging was performed in 251 patients; 150 underwent MRI with diffusion-weighted imaging (DWI). A summary of diagnostic accuracy values is shown in table below. WB-CTP is highly specific with a high positive predictive value in all groups and has moderate to high negative predictive value. Positive and negative likelihood ratios were 21.24 and 0.5 in the whole group analysis.

Conclusions: Positive WB-CTP findings may warrant early intervention, including thrombolysis, while negative findings alone are not a sufficient basis upon which to confidently withhold interventions.

One-pot synthesis of an indole-substituted 7,8-dicarba-nido-dodecahydroundecaborate(-1)

Carbaboranes are increasingly used as pharmacophores to replace phenyl substituents in established drug molecules. In contrast to traditional organic chemistry, elaborate procedures to introduce functionality frequently fail in the case of carbaboranes and their chemistry is often hampered by degradation of the cluster. Herein, the development of a one-pot synthesis of a water-soluble N-nido-dicarbaborato indole is presented, including a proposed mechanism for the reaction sequence. These studies provide useful synthetic tools for the conjugation of two important pharmacophores, indoles and carbaboranes.

Role of electrophysiological studies in predicting risk of ventricular arrhythmia in early repolarization syndrome

BACKGROUND

The early repolarization (ER) pattern is associated with an increased risk of arrhythmogenic sudden death. However, strategies for risk stratification of patients with the ER pattern are not fully defined.

OBJECTIVES

This study sought to determine the role of electrophysiology studies (EPS) in risk stratification of patients with ER syndrome.

METHODS

In a multicenter study, 81 patients with ER syndrome (age 36 ± 13 years, 60 males) and aborted sudden death due to ventricular fibrillation (VF) were included. EPS were performed following the index VF episode using a standard protocol. Inducibility was defined by the provocation of sustained VF. Patients were followed up by serial implantable cardioverter-defibrillator interrogations.

RESULTS

Despite a recent history of aborted sudden death, VF was inducible in only 18 of 81 (22%) patients. During follow-up of 7.0 ± 4.9 years, 6 of 18 (33%) patients with inducible VF during EPS experienced VF recurrences, whereas 21 of 63 (33%) patients who were noninducible experienced recurrent VF (p = 0.93). VF storm occurred in 3 patients from the inducible VF group and in 4 patients in the noninducible group. VF inducibility was not associated with maximum J-wave amplitude (VF inducible vs. VF noninducible; 0.23 ± 0.11 mV vs. 0.21 ± 0.11 mV; p = 0.42) or J-wave distribution (inferior, odds ratio [OR]: 0.96 [95% confidence interval (CI): 0.33 to 2.81]; p = 0.95; lateral, OR: 1.57 [95% CI: 0.35 to 7.04]; p = 0.56; inferior and lateral, OR: 0.83 [95% CI: 0.27 to 2.55]; p = 0.74), which have previously been demonstrated to predict outcome in patients with an ER pattern.

CONCLUSIONS

Our findings indicate that current programmed stimulation protocols do not enhance risk stratification in ER syndrome.

Acute loss of vision in a young woman: A case report on psychogenic blindness

Background

Acute loss of vision needs urgent attention and treatment. We report on a young Ethiopian woman who experienced acute bilateral blindness. In the presence of normal ophthalmological findings psychogenic blindness has to be considered.

Case Details

A 21 years old woman was admitted to the psychiatry clinic at Jimma University specialized Hospital, Jimma, South West Ethiopia. She had not been able to see for a few days. Ophthalmological and neurological examinations showed normal findings. No severe psychopathology was found. Stressful life events had preceded the appearance of the symptoms. An attitude of accepting the perspective of the patient of a seemingly organic disease is a precondition for a successful intervention. Treatment aimed at a gradual return to normal functioning. The patient regained her sight and fully recovered. The final psychiatric diagnosis was psychogenic blindness.

Conclusion

The psychosocial intervention was successful and encouraging for the patient and clinicians.

Prognostic Implications of Intraoperative Radiography of Thyroidectomy Specimens

Objectives:

(1) Analyze radiographic findings of thyroidectomy specimens. (2) Correlate intraoperative radiography to preoperative ultrasound and its guided fine-needle aspiration biopsy, intraoperative impression, and final pathology. (3) Describe a new intraoperative tool to help identify malignant characteristics of thyroid tissue.

Methods:

Prospective study comprised of consecutive patients undergoing hemi- or total thyroidectomy in a tertiary referral center. This is an ongoing study of patients treated from the months of November 2013 to June 2014. After obtaining ultrasound-guided fine needle aspiration biopsies that were indeterminate or confirmed malignancy, all patients received either a hemi- or total thyroidectomy. Prior to pathologic processing, the specimens were passed off the field and underwent intraoperative specimen radiography (IOSR) by the Faxitron Biovision (Tucson, Arizona), generating a plain radiograph. Radiographic characteristics were analyzed by a surgeon and radiologist and correlated with final pathologic diagnosis. Sensitivity, specificity, positive and negative predictive value, and accuracy of IOSR with regard to final pathology will be reported.

Results:

Adequacy of resection of tumors and the presence of microcalcifications are features assessed by IOSR which, when compared with a pathology gold standard, may allow for a intraoperative decision regarding surgery. This technology may reliably detect multifocal microcarcinomas, another indication for total thyroidectomy. This approach may reduce the number of diagnostic hemi-thyroidectomies that require a later completion thyroidectomy.

Conclusions:

Intraoperative plain film radiography may be an effective tool in the risk stratification of thyroid specimens and could be used as an adjunctive measure to reduce the need of delayed completion thyroidectomy, depending upon permanent pathology.